Template matching is a process of searching an input signal for a partial signal (target) that matches any known template signal, and specifying the position of the target (matching position) thereby. With such a process, matching computation is repeatedly performed between the partial signal extracted from the input signal for the computation use and the known template signal while the partial signal for the computation use is being moved in position for extraction. Thereafter, the results of the matching computation at the respective positions in the input signal are compared in size with one another so that the matching position is specified.
Moreover, for the matching computation, used are the well-known cross-correlation algorithm, the sequential similarity detection algorithm, and others (as an example, refer to Patent Document 1). Such algorithms are those for computing the signal strength for the partial signal for computation use and the template signal in terms of their correlated positions, and compiling the result for the signal in its entirety.    Patent Document 1: Japanese Unexamined Patent Application Publication No. H5-81433